The present invention relates to a ratchet tool that has a control member engaged with the pawl and a torsion spring 34 is engaged with the control member.
A conventional ratchet tool is shown in FIG. 1 and generally includes a ring-shaped head 40 and a toothed member 42 rotatably received in the ring-shaped head 40. A pawl 41 has a toothed surface engaged with the toothed member 42 and a spring 43 is connected between the pawl 41 and a control member 44. The control member 44 is rotated by the user to engage one of two ends of the pawl 41 with the toothed member 42. Each of the two ends of the pawl 41 allows the pawl 41 to rotate a with the toothed member 42 or to move over the toothed member 42. The spring 43 tends to reach its fatigue limit after a period of time of use. Besides, the direction of change for the ratchet mechanism often fails because the control member 44 cannot be rotated to a proper position.
The present invention intends to provide a ratchet tool that has a simple structure and is able to properly position the pawl member to perform desired functions.
In accordance with one aspect of the present invention, there is provided a ratchet tool and comprising a shank and a ring-shaped head which has a toothed member rotatably received therein. A recess is defined in an inner periphery of the ring-shaped head and a pawl is received in the recess. The pawl has teeth in a front surface thereof so as to be engaged with the toothed member, and a spring biases a rear surface of the pawl. A chamber is defined beside the ring-shaped head and communicates with the recess. A control member is received in the chamber and has a protrusion which is engaged with a notch in a top of the pawl. A curved slot is defined through the control member and a shifting lever is connected to the control member. A torsion spring has a leg fixedly connected to a hole in the control member and the other leg of the torsion spring is located in the curved slot.
The primary object of the present invention is to provide a ratchet tool that has a flat control member and a torsion spring to achieve the ratchet purpose.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.